In concrete forming, to construct walls and the like, it is common practice, to construct a temporary form from lumber, or other materials, to provide a retaining space into which concrete alone, or in combination with other materials, is poured in its fluid condition, after which the concrete is allowed to set. After the concrete has set to a predetermined solid form capable of supporting itself, the form is stripped away. Sometimes, the surfaces of the concrete are cleaned and patched to give a smooth surface if that is required by the job specifications. The forming material is hauled away, perhaps to be discarded, or to be used on another job site, if the forming material can be so adapted.
Because of the considerable hydrostatic pressure that is created by the concrete when it is poured to any reasonable depth, considerable lumber, or other materials, and sturdy construction of the forms are required to provide the necessary strength to retain the heavy concrete. Considerable time and hence expense is required by carpenters or other assembly men to construct the forms which in the end serve only a temporary purpose, namely, retention of the poured-in-place concrete until it has set to a strength strong enough to support itself.
The result of this conventional method of forming concrete walls and the like usually gives an uneven surface showing the imprint of the form itself. Further, the concrete often is not tamped into all areas of the form sufficiently, thereby causing depressions, gaps or other imperfections in the poured-in-place concrete. These imperfections must subsequently be repaired by a cement patching technique which involves extra time and expense. Further, when the concrete forming technique described is used, decorative finishes to the concrete surface cannot be provided without further work and procedure.
The applicant is the owner of two Canadian patents, Canadian Pat. Nos. 922,495, granted Mar. 13, 1973, and Canadian Pat. No. 941,588, granted Feb. 12, 1974, both naming John Rudichuk as inventor. These two patents disclose and claim a wall forming system that comprises a series of wall elements that are laid in superimposed courses in two parallel rows, to provide a pour space therebetween. The two parallel rows of elements are held in place by a system of H-hooks. When the parallel walls have been erected with the H-hooks in place, the fluid concrete is poured in the pour space between the parallel walls and is permitted to set. The concrete sets with the wall elements and H-hooks in place to provide a unitary wall system.
In the Rudichuk wall system, the wall elements must be constructed to close tolerances with holes therein for receiving the legs of the H-hooks. The H-hooks must also be constructed to close tolerances so that they will fit in the holes in the wall elements. The holes in the wall elements and the close tolerances required increase the basic production cost of the wall elements and the H-hooks. The protruding legs of the H-hooks also slow erection time because the holes in the wall elements must be carefully fitted over the legs, a time consuming procedure. Furthermore, the wall elements are flat on the top, bottom and end surfaces and hence when they are placed in abutting relationship with each other, there is no barrier to the passing of moisture between the respective wall elements.
To provide further background for the invention, the following is a list of United States and British patents that disclose and claim various systems for forming walls using wall elements and various tying systems:
______________________________________ U.S. Pat. No. Inventor ______________________________________ 2,029,082 Odam 2,181,698 Langenberg et al. 2,372,038 Westveer 3,238,684 Wood 3,562,991 Custusch ______________________________________ British Patent No. Inventor ______________________________________ 266,956 Bemis ______________________________________